Adolescent girls living on the streets have been overlooked in the past but the unique challenges they present are galvanising NGOs and children's rights experts around the world to formulate responses adapted to their needs.

"When we talk about street children, we generally mean boys," said Chris Rose, the co-founder of Street Child United. "Typically, street children have male associations for reasons that may be historical or demographic. But we need to ask: why aren't our programmes more successful with girls?"

Rose put that question to delegates from 20 countries at a recent conference on a street-connected children in Cambridge, England.

Leonora Borg, from the UK-based Consortium of Street Children, said: "Working with street girls, particularly adolescent girls, is very challenging. They drop out of programmes, they are hard to engage, their programmes are expensive and they have a multitude of issues. A lot of people ask: where do we start?"

Delegates tested a sample of a CSC toolkit for designing programmes for adolescent girls, which the consortium is developing with 20 organisations from eight countries and is scheduled to launch in March. Its guiding principles included allowing girls to complete programmes in their own time to tackle the high dropout rate, encouraging a holistic approach to girls' needs even when a programme has been designed to target a specific issue, refusing to be driven by donor demands and empowering girls by building their confidence, independence and choices.

It is known that street girls everywhere are at high risk of violence, abuse and sexual exploitation but their low visibility makes it hard to engage with them. Bonakele Mbaly, from NGO Umthombo in Durban, South Africa, recalled her own time living on the streets after fleeing an abusive stepfather, and spoke about her outreach work looking for girls who work as prostitutes at night."It is hard to persuade them to leave the streets because often boys are in charge of them," she said.

Vicky Ferguson, of Kenyan charity Glad's House in Mombasa, noted the vulnerability of this group, saying street boys and girls need separate spaces because the same boys are sometimes the abusers of the girls.

From Toybox, in El Salvador, Ada Milca Ayala stressed the importance of listening to what adolescent girls had to say about their own lives, citing her charity's emphasis on self-care after girls said they suffered in the intense heat and pollution of the streets.

Many delegates said that reintegrating girls into their families is particularly difficult because of factors such as domestic servitude, prostitution and trafficking, and may be especially hard in some cultures because of social stigma. Paul Sunder Singh, from the Karaunalaya Centre for Street and Working Children in Tamil Nadu, India, said his charity eases girls' reintegration into their communities by telling neighbours that they have been away studying at a hostel in another city. Souhair Mourad Milik, of NGO I, the Egyptian, in Cairo said girls might be ostracised after just one night away from home. Pete Kent, from Railway Children in east Africa, said it was important for NGOs to ask: "What is the intentionality [of taking a girl home]?"

According to the human trafficking expert, Abigail Stepnitz, NGO leaders should examine their own organisations for gender bias, in order to give street girls the best chances in life. "One of the easiest ways to show that progress is not preconditioned by gender is example, example, example," she said.

"Do women hold positions of leadership? Do they see men and women in the community with a gender/power imbalance? That is how you empower young people to resist stereotypes," Stepnitz said.

Bernardo Rosemeyer, the founder of Brazilian charity O Pequeno Nazareno, in north-eastern city of Fortaleza, said that, in his view, "Girls suffer differently from living on the streets. [In Fortaleza], boys who live on the streets have two possible fates: they either end up dead or they go to jail. The girls do not leave the streets."

The exact number of children living on the world's streets is impossible to quantify but is believed to run into tens of millions, possibly even higher than 100 million, according to Unicef.

The 2010 Street Child World Cup in South Africa resulted in the Durban declaration on children's rights, which was presented to the UN committee for human rights. Girls taking part produced a "Street Girl's Manifesto," which was published as part of Plan International's 2010 "Because I Am a Girl report on the state of the world's girls.

The Cambridge summit was in part a planning event for next year's Street Child World Cup in Brazil, an international football tournament involving teams of 200 former street children that will take place in Rio de Janeiro, in March 2014, before the Fifa World Cup.

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